English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Both the mass and radius of the millisecond pulsar PSR J0030+0451 have beeninferred via pulse-profile modeling of X-ray data obtained by NASA's NICERmission. In this Letter we study the implications of the mass-radius inferencereported for this source by Riley et al. (2019) for the dense matter equationof state (EOS), in the context of prior information from nuclear physics at lowdensities. Using a Bayesian framework we infer central densities and EOSproperties for two choices of high-density extensions: a piecewise-polytropicmodel and a model based on assumptions of the speed of sound in dense matter.Around nuclear saturation density these extensions are matched to an EOSuncertainty band obtained from calculations based on chiral effective fieldtheory interactions, which provide a realistic description of atomic nuclei aswell as empirical nuclear matter properties within uncertainties. We furtherconstrain EOS expectations with input from the current highest measured pulsarmass; together, these constraints offer a narrow Bayesian prior informed bytheory as well as laboratory and astrophysical measurements. The NICERmass-radius likelihood function derived by Riley et al. (2019) usingpulse-profile modeling is consistent with the highest-density region of thisprior. The present relatively large uncertainties on mass and radius for PSRJ0030+0451 offer, however, only a weak posterior information gain over theprior. We explore the sensitivity to the inferred geometry of the heatedregions that give rise to the pulsed emission, and find a small increase inposterior gain for an alternative (but less preferred) model. Lastly, weinvestigate the hypothetical scenario of increasing the NICER exposure time forPSR J0030+0451.

A NICER view of PSR J0030+0451: Implications for the dense matter equation of state